/Engine/Plugins/Runtime/CommonUI/Source/CommonUI/Public/CommonButtonBase.h
Returns the dynamic instance of the material being used for this button, if it is using a single material style.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, BlueprintPure, Category="Common Button|Getters") [UMaterialInstanceDynamic](API\Runtime\Engine\Materials\UMaterialInstanceDynamic) * GetSingleMaterialStyleMID() const